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Diffstat (limited to 'arch/x86/kernel/cpu/amd.c')
-rw-r--r--arch/x86/kernel/cpu/amd.c29
1 files changed, 25 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index e44338dd62dd..9862e2cd6d93 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -558,8 +558,12 @@ static void bsp_init_amd(struct cpuinfo_x86 *c)
static void early_init_amd(struct cpuinfo_x86 *c)
{
+ u32 dummy;
+
early_init_amd_mc(c);
+ rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
+
/*
* c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
* with P/T states and does not stop in deep C-states
@@ -622,6 +626,27 @@ static void early_init_amd(struct cpuinfo_x86 *c)
*/
if (cpu_has_amd_erratum(c, amd_erratum_400))
set_cpu_bug(c, X86_BUG_AMD_E400);
+
+ /*
+ * BIOS support is required for SME. If BIOS has enabled SME then
+ * adjust x86_phys_bits by the SME physical address space reduction
+ * value. If BIOS has not enabled SME then don't advertise the
+ * feature (set in scattered.c). Also, since the SME support requires
+ * long mode, don't advertise the feature under CONFIG_X86_32.
+ */
+ if (cpu_has(c, X86_FEATURE_SME)) {
+ u64 msr;
+
+ /* Check if SME is enabled */
+ rdmsrl(MSR_K8_SYSCFG, msr);
+ if (msr & MSR_K8_SYSCFG_MEM_ENCRYPT) {
+ c->x86_phys_bits -= (cpuid_ebx(0x8000001f) >> 6) & 0x3f;
+ if (IS_ENABLED(CONFIG_X86_32))
+ clear_cpu_cap(c, X86_FEATURE_SME);
+ } else {
+ clear_cpu_cap(c, X86_FEATURE_SME);
+ }
+ }
}
static void init_amd_k8(struct cpuinfo_x86 *c)
@@ -740,8 +765,6 @@ static void init_amd_bd(struct cpuinfo_x86 *c)
static void init_amd(struct cpuinfo_x86 *c)
{
- u32 dummy;
-
early_init_amd(c);
/*
@@ -803,8 +826,6 @@ static void init_amd(struct cpuinfo_x86 *c)
if (c->x86 > 0x11)
set_cpu_cap(c, X86_FEATURE_ARAT);
- rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
-
/* 3DNow or LM implies PREFETCHW */
if (!cpu_has(c, X86_FEATURE_3DNOWPREFETCH))
if (cpu_has(c, X86_FEATURE_3DNOW) || cpu_has(c, X86_FEATURE_LM))